Yeah he's taking his own Sansamp just in case no one else has a DI box. It's serving the same role as a "house amp" would do.
I'll be taking the Tonex One and a passive DI box.
FWIW, I am actually pretty happy I'm not having to take an amp - from memory this venue sounds pretty good and has great bass response, and last time I played there (I was on rhythm guitar at the time), my Marshall DSL40CR and chonky pedalboard were a nightmare to get up and down the 3 flights of narrow twisty stairs. Now I can just take one gig bag with my bass, IEMs, Tonex One and some cables and I'm done.