Can other members suggest places they have busked where they’ve made biggest bucks?
Places where people gather for lunch, where you get a lot of foot traffic but not foot traffic that’s in a big hurry to be somewhere else.
Dionys
local shopping malls are not too bad if you get permission from the mall management prior to playing. Folks coming/going around the entrances usually will take a minute or so to listen and even throw a few coins. Also the advantage of a shopping area is you can switch around to different entrance/exit areas. 
where are the hot spots is the states and canada for busking?
City parks can be good, but be advised that in the U.S. some cities/states require permits for ‘busking’ in a public place. It’s probably a good idea to check into this before getting fined.
I have in Malls before without permission and nobody (as in security) really seems to care I have made $3-$10 within Half an Hour this was on high whistle, low whistle, and Irish Flute so I don’t know how you would fair on the pipes. 
In my personal experience, bagpipes (of any variety) generally tend to fare better in the tip department. Last time I piped for tips was 6 years ago at a rennaissance fair, and a half hour of playing netted me $250.00. Pretty good wages if you ask me.
Traditionally one of the best places to busk here in Ireland was at race meetings(horses that is).Plenty of drunken punters with big bucks in their pockets
where are the good spots to busk in new york/boston?