lIf he were truly lazy, he'd have a full-on beard. If you're !$%*!$%*!$%*! then you have to go to the trouble of shaving your whole face (well, anywhere where facial hair grows). If you have a full beard, then you have to worry about !$%*!$%* it periodically. But if you havea goatee, you have to both shave _and_ trim - you just don't have to shave as much of your face or trim as much beard. Personally, I'd think that out of !$%*!$%*!$%*! full-beard, and goatee that goatee is the most trouble and least lazy option - which is highly un-Wally. Trying to get some benefit from the look is very Wally though.
Oh, that's a Van Dyke not a goatee. "A Van Dyke consists of a mustache and goatee. Optionally , it may also include a soul patch." (from Wikipedia) I guess that evil twins having a Van Dyke comes from the Star Trek episode "Mirror, Mirror."