MaizieD
when I started secondary school we had an antiquated English teacher whose mantra was 'all right is not all right unless it is spelled as two words'. Nowadays everyone spells it as 'alright' without a second thought. I think that bowlsful has made much the same progression. I'm sure that it would originally have been two words, 'bowls full' and we've just got into the way of running them together. Having turned them into one word people are doing what seems to be the rule with a plural noun and putting the 's' at the end of the word.
My spellcheck objects to 'bowlsful', BTW. It offers me 'bowlfuls'
P.S I think that 'a lot' is going the same way., alot
Going off on a tangent, I would also like to complain about the similar way that "any more" has started to be joined up into one word.