[soulofmischief]

Ha, yeah there's a lot of snake oil in the business.

However, there is definitely a difference in sound, however subtle to some, between most tube and solid state amplifiers when it comes to recording music, as musicians tend to try to draw out certain sounds that are a consequence of the design of the amplifier, whether by overdriving the input or exploiting analog flaws, etc.

Even when comparing just tube or solid state amps, there can be a lot of variance between them.

This doesn't really apply to consumer-grade amplifiers where the goal is perfect sound reproduction. A good tube amp and a good solid-state amp shouldn't sound different to an untrained ear. But amplifiers used in production often try to differentiate themselves in some way sonically.