Also these coins have the block time of 60 seconds not 10 minutes which means transaction are confirmed very faster than bitcoin, makes it even usable in fast food stores for example.
I think typically fast food drive thru lines aim to have each customer through the line within 2 minutes. Potentially adding up to 1 minute (or more if a block doesn't meet target) of wait is not good. A crypto that wants to be able to compete with a Visa purchase in a store needs to go through in a few seconds. Like less than 5. More than that is too much.