There's also a chance that you can find them in Yue's store. I lucked out that way- yeah, they cost 50k or so, but they're totally worth it. I dunno how rare they are... but I started seeing them after Oddward Valley, and I've seen them in her inventory three times. (Compared to never, on the pineapple seeds.) They're much easier to use than that stupid lily pad- obnoxious on/off boarding and an inability to store it, lest you use up the daily use.
I carry mine around everywhere- they're great for the water patches you've forgotten about. I can think of Pia and Zaid, at least, who have quests which turn out to require water walking. It's also nice to fight the boss monsters on Priviera's Hidden Island without worrying about losing the lily pad. You can walk up to the island, switch footwear so their attacks can't knock you off-screen, and repeat the process since there's no dumb daily limit.
As far as the Wi-Fi prize goes... you're more likely to get to craft level 4x with a 10% chance than you are to get enough points. That's my experience, anyway. Admittedly, I was bad about carrying surplus cash around... but, still. That's my guess.