Bitcoin does indeed have a lot of infrastructure, but that advantage won't last forever. For example, there are more and more ATMs adding support for the major altcoins.
In October of 2017, 29% of all Bitcoin ATMs had support for altcoins, At the start of January, 35% had support for altcoins (https://steemit.com/bitcoin/@techwizardry/2017-ends-with-2000-new-cryptocurrency-atms-first-monero-atm-goes-live-in-texas).
I would say by the end of 2018, more than 50% of all Bitcoin ATMs will support ETH and Litecoin.
Very good point. This is exactly what im trying to point out.