Summoned XP not giving XP to players

I've been messing around with the new /summon command and found I can use it on XP Orbs, so I did just that in an automatic command block circuit.

What I expected to happen was...:
I expected that once I went into survival and got the orbs I would gain levels.
What actually happened was...:
I collected the XP but my bar did not go up.
Steps to Reproduce:
1. Make a command block circuit that constantly spawns XP orbs.
2. Go into survival and collect the XP.
3. No levels! :c