Have you maybe ever noticed that there is a difference between dogs, cows, cats, sheep, goats, horses...? Have you noticed that there is a difference between people when it comes to the way we behave to each other? If somebody punches you once in head you can sue him and maybe put him in jail. But if somebody keeps beating another person for ten minutes, hurting him badly, sending him to hospital, he is glorified as a world champion. If you sing a certain song in one country you'll be a hero, in neighbor country you'll go to jail, in some distant country nobody would care not even recognizing the song. If you drink wine you can be popular, you can be rejected as a drunk, or you can be stoned for breaking the law and insulting certain religion.
So if we act so differently to each other, how could we act equally to all the animals? Finally, if we should treat every pig and cow as our pet dog, does it mean the same for rats and cockroaches? They are animals as well, so how can we have double standards? Do you feed your rat regularly and do you let your cockroach lay on your bed?
Yes there are differences and some of them are pretty huge but in almost all societies Murder,slavery and rape are considered punishable crimes as would your example of someone beating someone else in the head for ten minutes ( i realize you are using boxing as an example but except under a very structured set of rules and conditions this behavior is not ok or encouraged) so yes there is a trend to adopting certain rules of behavior that have changed a lot over the last few hundred years so there is hope that one day we will treat animals a lot more fairly and stop eating them unnecessarily.
As for your second comment there is a lot of difference (at least according to the best information available today to suggest a major difference in the ability of mammals and insects to suffer ans when it comes to rats one could argue that due to their tendency to spread disease that some suffering might be necessary for an individuals survival (not that i have ever found it necessary to kill a rat myself) and most vegetarians would not argue against killing in order to survive rather than just because something tastes good.
Your argument is pretty weak and it is the protests of people who believe they are seeing others act immorally that have moved us forward as a society in the past and will do so in the future, so i for one will continue to point out to others wen i see them behave in a way i (and a significant minority of other folk) i consider to be wrong.