On-line deliveries, should I tip?

[treehugger]

I do a tesco shop once very 10 days - 2 weeks. Generally there are 5 or so crates. The guy has to come up 6 steps and then bring into my kitchen. In the past I have not tipped, but then I noticed that my husband (who always pays the takeaway delivery guy) pays him ?3-5 around about10%. Tonight I gave the Tesco guy ?2 on a ?113 shop. This was all the cash I had in my purse. So, question: was it too much, too little, unnecessary? Please let me know what you do, so I can get it right.