Are DVDs the real killer of video rental stores?

Not really. People go for what's convenient, not what's better. Streaming is more convenient than driving to a store in a snowstorm for a DVD, plus it's cheaper to pay a $10 subscription a month to view hundreds of movies, than it is to buy a $20 DVD/Bluray. I personally prefer physical media over digital, but I can see why it's on it's way out.

No, because the customers could still rent the dvd discs and return them just like they did with the vhs tapes

"I told my man I'm going to get a pap smear. he said 'bring me one no mustard'" - Adele Givens

Yeah I used to get annoyed by the fact that often if a movie was a 1-day rental new release I wouldn't have time to watch all the extra features (not even taking into consideration things like interactive features and audio commentaries) so I stopped renting a long time before all the stores started going out of business. I still kept buying ex-rental discs though!

I'm thinking just the internet in general is what killed video rental stores. When I was a kid, the big thrill of going to a video rental store was trying to sneak into the curtained off adult sections and try to rent a porno. Free porn on the internet eliminated the need for the porno section and the mom and pops shops in general. You weren't getting porn at Blockbuster and the mom and pops couldn't compete with their mainstream movie selection.

Porn might be the answer, combined with piracy by tech-literate young people who were probably the largest consumers of lucrative new releases. Video stores began dying off well before Netflix streaming became common.

It was a combination of things

-The internet became huge

-PPV got much bigger and the window of time between a video released and when a film hit PPV kept getting smaller.

-Premium Cable channels expanded. Instead of just having HBO, people now had HBO, HBO2, HBO Comedy, HBO Family... for the same price.

-Chain videostores like Blockbuster and Hollywood drove most of the smaller mom and pop stores out of business by being able to load up on 50-100 copies of the latest big movies. This also resulted in movies having a shorter shelf life as everyone could rent a new release within a week or two of release. It hurt business on catalog titles as people became conditioned to grabbing the week's new movies without even looking at the older stuff.

By the time DVD came along video stores were already dying out.

No, streaming and on demand have killed off most rental stores. DVD may not require rewinding, but it's still a piece of physical media that you have to return to the store. The only thing that is keeping certain stores alive (like Family Video) is that they get films before Netflix and Redbox.
Physical media is dying a slow death, but it will eventually fade into obscurity.

DVDs definitely have become so cheap that you might as well purchase the disc, and not have the hassle of scratched discs, returning and late fees. I'd say VHS is the same. In the 80s (so I was told) it was hundreds of dollars to buy the video. Then when they did become cheaper it was still $30+ for a new video. So you either do that or you pay $5 and rent it.

Now DVDs are $3-$20 more or less.