Megabus won't be my buddy

I tried to talk Megabus into letting me buy an extra seat to carry a packed up plywood people piece to the DC area, and they turned me down. Rats. It would have cost an x-tra $15.00, added to my $15.00 out, and $10.00 back. Then, I would have had to pay for one bus to get the couple of miles to Alexandria, VA, (maybe $1.00?) then one free trolley to the Torpedo Factory's Target Gallery. So much for my efforts to use public transportation. if this was South America, they'd even let me bring my free-range chickens!