It depends on who you fight, some players just camp or mash buttons in turn making you hate every character.
not really, if someone's mashing buttons or camping with a character that seriously doesn't excel at camping at all(or in the case of mashing buttons, just pretty much any character they play) they tend to play extremely bad, and are easy as hell to beat.
I love finding the ike noobs for instance in basic brawl, all they do is mash buttons frantically like maniacs and end up being so easy to slaughter, nothing provides a better satisfaction IMO than seeing an Ike noob who thinks he's op'd, and mashes buttons like a fool, only to get slaughtered in the process
Now of course if someone *IS* playing a character that is great at camping, and KNOWS how to camp effectively, THEN YES they can be extremely annoying, a falco who knows what he's doing can be a royal pain in the *** to fight.
but as far as mashing buttons go? nah, sorry those players are so easy to slaughter that i love running into em.