Quick web search shows cheapest 6 inch subway (plain ham) is $8 in Australia. From memory, couple of weeks ago I was paying around 110 baht or $4.90 at Jomtien subway (today's ex rate 22.3), but cheaper if you get the sub of the day. Nearest I'll get to real Thai food.
Of course, as others have already pointed out, Thailand is hugely cheaper for the things that really count, such as housing and services. I paid $270 in Oz for an electrician to change a light switch, 2 minute job (he gave me a $30 discount as I'm retired). Paid 120 baht, or $5.40, for a lady in Pattaya to fix the soles of my sandals, over an hour's work, and my apologies to some here, I tipped her 80 baht.