You're living in the past old pops. You also seem to be living in a fantasy land where everybody drives a car or rides a motorcycle.
If I want, say a pizza or two whilst I watch a movie then why would I hump the BTS then walk for 15 minutes in the sauna that is Bangkok, pick up my pizza then head home via the same route?
Pizza will be cold by then and I'll be all hot and bothered. Waste of time and money when all I have to do is fire up Grab, choose priority delivery and the nice, polite delivery man or lady will get it to me piping hot (most of the time) and without all the mess and fuss.
Also, calling the delivery guys grubby, well that's just sad man. They're just normal people trying to eke out a living. You're taking food off their table by not using them, or worse not leaving a tip.