I have been reading some accounts of people keeping shrimp with kuhlis perfectly, but Ive never done it!
with a male betta I would say fine, the kuhlis wont bother him, it just depends on his personality to be honest! my kuhlis are hardly ever out they are usually buried underneath the gravel or hiding under the bogwood...so chances are he may not ever see them, although peoples accounts of keeping them are different!
To the best of my knowledge only the 'botia' loaches such as clowns, yoyos, polkadot eat snails
hope that help a tad