Unions are not just for the purpose of getting fair pay, but rather about a broad case of being on equal footing with an employer, as stated in the parent comment. Besides, this union is not just for salaried google employees, but also contractors etc - this will include for example cleaners and cafetaria employees, which are much more likely to be in need of the sort of union support that you mention.

Google was one of the participants in a corporate wage-fixing scandal. Do snacks and foosball tables justify that?

and they got sued for that and lost. No union was involved in holding them accountable

Because there's no union who represents Google, Apple, etc. employees as a single cohesive block, there couldn't have been a union holding folks accountable. You're implying that the courts were successful, but only after Googlers had an employee revolt (read: a non-union-organized strike!) against being taken to forced arbitration.

Yeah, they got a small slap on the wrist for that one. My point is the presence of snacks and perks does not preclude the exploitation of labor.