The Gulls were given a flying start by new loan signing Gavin Tomlin.
The on-loan Dagenham & Redbridge striker celebrated his United debut by racing on to a through ball from on-loan Ipswich striker Ronan Murray before cleverly clipping the ball over Town goalkeeper Ben Smith.
Jermaine Grandison was sent-off for Shrewsbury and Robinson then struck from a 54th-minute penalty and doubled his tally two minutes later with a thumping 20 yard strike to make it 3-0.
Striker Chris Zebroski got a fourth in the 70th minute when he buried Craig Stanley's cross before Shrewsbury skipper Ian Sharps appeared to get the last touch to Stanley's cross-cum-shot in the 85th minute.
Source: PA
Source: PA