送到 is a resultative verb compound (动结式): 送 (to send/see off) + 到 (to arrive/reach) = to send or escort someone/something so that it arrives at a destination. It covers both 'to deliver (an item)' and 'to accompany/see off (a person) to a place'. You cannot separate the two characters with a complement in the middle — the result is already built in. Use it wherever the focus is on the successful arrival after the action of sending.