Merwyn had done a lot more for a lot less before now in his attempt to befriend the entire world, and that included things that he knew he didn't like and knew were dangerous; he'd rather be entertainment and kept around for that than ignored and forgotten. He was genuinely ready to try Seamus' suggestion though, tickled by the idea and even beginning to seriously consider his idea of putting them in his hair.
He pouted to hear that Seamus was too busy for a ten day birthday but pleased that the ice cream bar was a confirmed idea. He felt awkwardly rejected personally even though he knew it was just a rejection of his spending all that money (or thought it was anyway) and he nodded with a smile that it was okay. "If you're sure?" he asked, just to make sure. "You deserve it, looking after all those drunk people every night."