Most of the fim's 'plot holes' can be explained
(MAY CONTAIN SPOILER)
Many people who've seen this movie have criticized it, asking questions and pointing out what they consider to be gaps in logic. Actually, I think most of these supposed "logic gaps" can be filled in. I'll go over the different questions I've heard people ask.
1.THE HIGH COST OF STAYING AT DELOS
At the beginning of the movie we're told it costs $1,000 per day to stay in Delos. This would certainly be an outrageously high price and not something that anyone today who wasn't rich could easily afford. Remember, though, this film takes place at some indefinete time in the future. The filmmakers were probably taking into account continued years of inflation. Take, for example, the value of money in the 1930s versus it's value in 1973, or today. In the 30s, the average job only paid a few dollars for an entire day of work, and a guy could buy a burger or a ride on a streetcar for a nickle. Nowadays, a minimum wage job pays five to ten dollars an hour (exact amount varies from state to state) and one whole dollar is maybe enough to buy a candy bar. Now imagine continued inflation over the next few decades, where the prices of everything continue to get more expensive, but as a result wages continue to increace in order to keep up with the inflation. It's entirely possible, then, that $1,000 in whatever year this film is set in could well be roughly equel to $100 today.
2.ROBOTS WITH SWORDS
In Romanworld and Medievalworld we see the robots use real swords and engage in swordfights with the guests. People have asked why they would give robots actual swords since there's no safeguard against stabbing someone. Consider this: if you are having a mock swordfight with a trained professional, your opponent can take special care so as to not cut or stab you, only try to knock the sword out of your hand. There is no reason why the robots couldn't be programmed that way. The robots were given metal swords to add to the realisim of the guests experience, since if you're fighting with rubber swords you don't get the clanging sounds or the feel of metal hitting metal. (This also explains why the robotic rattlesnake in Westworld had metal teeth instead of rubber ones; it was never supposed to actually strike a guest, and the guys running Delos just never counted on it acting against it's programming.)
3.THE GUNS OF WESTWORLD
People have asked why give the robots in Westworld actual loaded guns, and why the guns are able shoot people later on dispite the built-in heat sensors. First of all, the robots were programmed not to harm the guests, and because of the heat sensors, the men running Delos never thought it would be a problem, so they just loaded all the guns and then gave some to the robots and some to the guests. Later on, the computer controling the robots malfunctions and causes the robots to turn homicidal. Also the heat sensors are controled by the computer, and they stop working around the same time that the robots start killing the guests.
4.SOME ROBOTS CAN DRINK, OTHERS CAN'T
When Peter and John first come to Westworld and have their first encounter with the Gunslinger, we see the gunslinger drinking whiskey. However, tword the end of the movie, Peter gives a slave girl in Medieval world water thinking she's human, and she short-circuits. This is because some robots were built with liquid-proof insides, others weren't. It makes sense that it would be possible, at least in the future, to make a robot that can "drink" fluids without suffering any internal damage, but that doing so would be more expensive. Thus some robots, like the gunslinger in Westworld, were made to be able to drink without any problem all for the sake of adding to the atmosphere for the guests, others, like the slavegirl in Medievalworld, weren't.
5.THE BAR FIGHT
OK, here's where things get alot trickier. Midway through the movie, before the robots start killing people, a bar fight in Westworld is instigated by the Delos techninians. The problem with this, of couse, is that there's no way to really control something like this. What if two guests get caught up in the excitment of the fight and end up beating each other senseless, each unaware that the other is another human? What if one guest slams a chair into another guest's back, or a guest has a chair thrown at his head? However, there is a scene where the Delos technitians are having a meeting discussing the recent technical difficulties they've been having, and one guy says,"There IS some danger, that's part of the whole appeal!" I suppose the Westwold guests would be warned ahead of time about the barfights and the risks of getting involved in them, perhaps they'd be made to sign a waver ahead of time stating that should they choose to partake in a barfight the heads of Delos would not be responsibe for any injuries that might occur.
6.PETER GOES TO JAIL
After their second encounter with the gunslinger, Peter is sent to Westworld's jail. You might ask the question, however, of why let yourself be taken to jail if you know the sherif can't actually shoot you? Perhaps John told Peter that it would be fine, that guests don't actually stay in jail for long, that he would be breaking him out of prison soon and that he should just play along.