Yes, it's relatively common. Hosts have historically made money by selling additional services such as SSL certificates. Many will charge you per time for adding a certificate ( which every few months, starts to add up). some will insist that you need to "upgrade" or "get a dedicated IP address" in order to be able to add your own SSL certificates.
On the other hand, there are plenty out there who will either let you upload / install your own certificate, or even better actively support Let's Encrypt and make it automatic for you. Have a look at https://community.letsencrypt.org/t/web-hosting-who-support-lets-encrypt/6920 for a list of some hosts who do this - you might find something that fits your requirements there.