Yeah, sort of, it was not gift I think, he bribed them. What Harry did was bribing them to some effect because he valued their past & future help.
The cause of fealty for wyld faes is probably different than what we know of the courts. Although from their lack of creepiness nature, I'd tend to think they'd have to be descendants/creatures from Summer's side, Toot toot & co were independent IIRC since they were ignored by both sides (perhaps no one thought they'd be useful for anything), it's likely that their fealty is theirs to give, that for any type of (independent) wyld faes it's just a matter of being left alone or end up at the mercy of Winter or Summer sidhes' will. So unless given or taken, nothing binds them, which means no obligations to pick court sides, unlike faes who were born from the bloodlines of both courts (or maybe just sidhes, creatures don't have that much freedom).
But I strongly suspect it's deeper than just transactional level of bargains, once they pick/get picked they can't switch to any other side.
I don't think you can bribe the Fae, you can bargain.
When Harry entraps Toot, he offers him a bargain: Give him information, and he'll release Toot.
It's an exchange of value. The Fae seem to be something like TFM fundamentalists in this regard- they have to keep their word. Mab frequently talks about balancing the scales.
I rather think that Harry's open-ended, non-negotiated gift of pizza means that the scales were balanced at the rate of how the Little Folk value pizza, not how Harry values pizza or pizza is objectively valued. If you bargain poorly, that's on you, and that's how the Fae grow; either clever bargains or loaning out renewable resources.
As to the alignment of Wyldfae, this is explained by Toot himself in Summer Knight. When the Courts move to war, the Wyldfae find themselves drawn karmically to whichever Court is closest to their most recent behavior (the line is something like "if you've been doing mean stuff recently, you go to Winter")- the dewdrop faeries are normally Summer aligned, but Toot's group at that point are loyal to Harry.
Reading Summer Knight, it's not clear if the dewdrops were in the bag with the boxcutters, or Harry was able to summon them. Mab specifically notes that "it is rare for a mortal to be able to Call the Fae"- note the capitol? I think, even this early, that the Summer and Winter Courts sent out a call to the Wyldfae to join the court most closely aligned with their loyalty- and the proto-Guard showed up at Harry over *either* Court, and he was able to "Call" or summon them to him to defeat Aurora.