I think the poem falters in the second stanza. The first stanza is perfect. The first line of the 2nd stanza is perhaps clunky. I think a metaphor is needed here and not a simile. The last line is striking. The poem isn't perfect in my estimation and I like many of Simic's poems.
I love the wit of the piece, with it's emotional sucker-punch of a last line. The idea of your best alone, because of an imending scramble for seats is friggin brilliant. I like this plebian sort of poetry.