It wasn't from surveys. The WDW walk around characters were getting swamped with tourists and alterations were an issue because of the lack of a formal queue set up.
As I said, there's a noticeable difference in how people behave between Anaheim and Orlando.^^^^^
This
Stupid tourists in Orlando can't help themselves...they just have to push and shove and swarm the characters and touch inappropriately...
If only people were as decent down here as they are at the other Disney resorts, we might actually have free roaming characters still.
However I think part of it also is to be chalked up to the fact that Magic Kingdom sees more guests than Disneyland and and has significantly fewer attractions, leaving more people with less to do.