As heavy gunner it helps to control the accuracy of your shots and you
still get the suppression fire you want.
A paintball marker doesn't have recoil compared to any firearm design. I can fire my TM7 on fully automatic for a hopper plus and it's still controlled accuracy (granted, it's wasteful, and I'd never do it... but I CAN do it if I really wanted to)
Burst was actually developed for when people got ambushed to defend themselves and not use auto. It gave fire power, found to be more accurate and had overall better results than auto for assault rifles.
It never replaced semi it just replaced auto.
There are two problems with a 3 round burst I can see. One is paintball specific and one is not.
1. Paintball specific - a lot of the "burst" modes fire 3 paintballs per trigger pull. In the real world, if you let go of the trigger before 3, it stops firing. The burst mode becomes a potential hazard because you always have 3+ shots flying downrange.
2. Not paintball specific - It amounts to a training issue. The only difference between "burst" and "automatic" is that burst will stop before automatic does if someone just holds down the trigger. Train to release the trigger after 3-5 shots on fully automatic and the problem of muzzle rise is virtually gone anyway (or at least no worse than a "burst" mode).
On a related note, the US is going back to "automatic" over "burst" in the military. In a few years, they'll be retiring the existing rifles for ones with automatic trigger assemblies.