Who Me Too'd this topic

I am new to Spotify, so my account is linked to Facebook and my "username" is an arbitrary series of numbers.  Some of my friends, who are older users with custom usernames, have opted NOT to connect their Facebook accounts with their Spotify accounts.  I know that I can search for them if I have their usernames by using "spotify:user:username" in the search bar.  Since they are not alerted when I add them, how are THEY supposed to locate ME in return?  Is the only way for them to search for me (searching by spotify:user:username), plugging in my random numerical "username"?  Or can they locate me by searching with some other, more rational identifier (like my full name or email address)?  (As a side note: I had intentionally deactivated my Facebook over a year ago because I do not care to use it, and was forced to reactivate it in order to use Spotify.  In order to maintain my privacy, I had to dramatically alter the contents of my Facebook page since you forced me to make it active.  This was extremely burdensome, and I despise forced Facebook integration in general.)