I had a large pearl gourami in my tank years ago. He didn't make the move He was similar, though he never did it constantly.
The two clown loaches I have are the most personable fish I have ever seen. I used to get them snails. You know how allot of stores plant tanks have snails? I would go in and they would give them to me allot of the time. Or I would buy a plant I didn't need and scrape the snails of off it. There is a "popping" noise clowns do sometimes, I think it is a puff of water to dislodge the snail from the glass. They would swim up to the glass and do this when I walked in with the bag. They didn't do it when I fed them their regular brine, mysis, or anything else. Those two knew and got excited when they saw a bag from the fish store.
Though, they did do this when I brought home a clown knife, I assume they recognized the bag. They were never nice to that guy, he only made it a few months.