Premature Conclusion from Personal Experience
There are no arcades where I live. There are only a few in the entire country and not a single one has a CvS2 or 3S machine. So to me it's a big deal when I do see one of those. I was in LA in fall of 2004 for my internship and during that time I made several trips down to Family Fun Arcade. Thanks to Mike Z for giving me a ride and putting up with my lame jokes. I also got a chance to play a bit at UCLA's in house arcade. I can honestly look back at that 3 month period as being the time I played the best 3S I've ever played. And now I think I know why.
When you're in an arcade the atmosphere is great. It's much more fun than sitting in some guy's living room with a stick on your lap. The people around you make for great conversation, but they also create an audience, an audience you don't want to disappoint. It's only light pressure but it helps. The format is also very different, you don't play as many matches as you do in console meetings nor do you play them in a row. Unless of course when you win, then you get to stay on obviously. My best streak while at FFA was 8 wins iirc, but not against the better players. Yay? When me and Anecdote play CvS2 we can go for hours on end, cranking out 150+ matches, by the end of which the play has gone way past its peak. In an arcade you've got to make the most out of the games you get, you have to focus more by design. A quarter isn't much, but if you're a cheapskate like me you'll care what value you get out of the 25 cents you pay per game. As if that weren't enough, you get instant feedback, not allways useful and most definitely not allways appreciated, but it can be useful as well. You can hear the croud cringe as your opponent blocks your wakeup super and you can hear their amazement as you guess right on a mixup 3 times in a row.
All in all, Arcades are the perfect setting to put you in the right mental state to perform. Maybe it's just me and how I approached it. Considering how rarely I play in arcades I might have been extra psyched when I was there. Who can say, but I'm still convinced; arcades make you play better.