You won't have to pay $100 to open a channel. It requires one onchain transaction. Send a SegWit transaction (which will have lower fees than a current one, current transaction fees being about $1 if you use a median size transaction at the lowest fee that could get confirmed), and then you can send an unlimited number of times.
If you do the transactions with your coffee shop each day, receive funds from faucets or signature campaigns or other relatively small payments, your fees will reach less than 1% very quickly.
The difference is that LN makes the transactions happen instantly without the possibility of double spends. It's like comparing a credit card with wire transfers - one happens quickly and easily but is less secure, and one takes longer but is more secure. In everyday life you need both.