Anyway, yes it is bad etiquette and I don't recommend doing it at all since at the higher levels (or even at 5/10 PLO), people won't be willing to play you if they know you'll go south with their money. 5/10 PLO doens't have all that much different players and you see the same faces a lot, you'll get tagged and people will recognize you. Sit another round of blinds (or two) and then quit: hit and running all the time will become very -EV in the long run since people will try to run you over, deny you action, wich will eat at your winnings much more than 30$ out of a 1.2k pot.
If you're playing PLO this above is the real and
only reason you shouldn't hit and run, because the pool of players isn't exactly very large at 5/10 and in the long run it will hurt you because you can be sure they
will remember.
I say its the only reason not because I don't believe in etiquette, but because online is full of these players, many of them are actually of the variety that don't even wait for their BB. A few months ago when I started playing
real money this type of behavior would make me upset, but it no longer does. I actually find it funny now when after taking down a pot they don't even stay to look at the next hand their dealt. Part of the reason why I don't care is that I play holdem so usually the player that leaves gets replaced quickly. Of course you would like a chance to get your money back against the same player (cause in many instances its a donk that got you on a bad beat) but there is nothing you can do.
Having been a victim of this many times, I understand the message some of the posters here are trying to deliver but online its pointless to try and teach etiquette to the large mass of lowlifers that populate these games. It's like preaching in a desert. Just look at what happens when people can't get a password for a freeroll. Some of the common sense table non written rules listed by Rammer Jammer that constantly get broken are, to a certain extent, even worse than hitting and running.
However, all that I said above applies mostly to low limits. Even if I haven't played high limits I'm quite sure that the higher you go the more it will resemble B&M type of environment, therefore hitting and running should not be a part of your repertoire. Not to mention that the pool is considerably smaller, and if you do this consistently you might struggle to get action. Occasionally I watch high limit limit games and I've noticed how players with a big stack sit out, leaving the money on the table and not banking it, and then later on sit in again and play.
I would suggest, since you play PLO 5/10, not to repeat this type of behaviour because in the long run it will damage you. What makes it worse is that the likelyhood of your opponents, in those levels, pulling this to you is much smaller compared to the lower limits. Had this been at a $0.25/$0.50 table I would have told you to don't even bother answering the guy that was berating you, since at those stakes the hit and run is pretty routine. The fact its low stakes doesn't make it right, but you'll be a victim of it so many times that you won't lose your sleep for (incorrectly) doing it.