There are lots of scenarios that requires a quick transfer of coins, as long as the coin is wider accepted, like USDT the stable coin. So lightning payment network just provide more options to users.
For example, online games, where users may exchange coins quickly because a round of game wont wait minutes for a mainchain confirmation.
Another scenario is typical: off line store selling coffee/book/electronic device etc. Paying by BTC is an option, but what if by coupons or digital legal tender if local regulation permits.
I think lightning technology shall be applied to real businesses subject to regulation. So that various type of coins shall be suported. Shit coins will not be accepted by users, there wont be many shit coin channels in OmniBOLT network, so that we dont need to worry about that.
Are you saying that there will be NO reason to HODL altcoins, because Bitcoin WILL copy altcoin features through its development in the Lightning Network? I support!