I fish mostly from the bank - and as long as the boater attepts some curtisy - I have no issues. Usually this simply means drifting quietly by. I'm usually not too concerned about where he passes.
Now for jet boats - it would be nice if they slowed down a little - but on a crowded river - they'd be constantly working the throttle - and I'm sure it's just easier to pass by quickly and let everyone get back to business.
No bankie likes to share his hole with a boat, but on a large river, some holes are quite easily shared. I would hope that unless this is the only (or best or whatever) hole that the boater can or plans on fishing, that he would just move on to the next one. The bankie is usually very limitted in the amount of water he can cover in a day -where a boater really loses nothing by passing by an occupied run.