Right, BUT. What is allowed in MySQL isn't necessarily going to follow ANSI SQL or standardized 'best practices'. In other words, saying "its not bad SQL" isn't the same as saying "well, MySQL let's you do this...". It's sort of like PHP and data types. PHP is very weakly typed, but forgiving and very easy to work with. There's a trade-off.

We could argue about it all night. If you want to wrap your INT type data in quotes, I won't report you.