Sammy and 'Mantha must love each other very much, despite the fact that they must have built their relationship around them having the same name. They must love each other because Sammy is a raging alcoholic. He goes all the way to Russia and spends all his time getting drunk on Vodka. He saw absolutely none of the sites, leaving poor 'Mantha to traipse round Moscow on her own. Lynne knows this would happen by the way she asked her second question. But let's give Sammy his dues. He earns enough to take him and his wife to Russia in the late 70s.
Sammy is so drunk now that he's saying 'Cheers' to no one. Maybe he's just happy because he has on his favourite Spiderman slippers.