An increasing number of digital-asset startups are offering airline-like loyalty points as they seek to attract more devoted users, even though most have yet to define what the rewards actually entail.

Loyalty programs have sprung up in response to a once-favorite marketing ploy — the token airdrop — in which projects give away crypto tokens to users. But the industry is rethinking this tack because many airdrops have done little to retain users while regulatory scrutiny has swelled over tokens themselves.