Sorry, don't agree with this statement. The lads and lasses that look after racehorses every day are very attached to them and care very much about them.
The racing lads and lasses spend a lot of time with their charges - how many 'pet' horses are groomed for an hour each day? Walked in hand to graze? strapped? Having done racehorses I know they not only love those horses as their own but care deeply for them.
