That's her choice Jacqui. There are hundreds of housewives who do it for pin-money. It's an ideal job for someone who's surrounded by neighbours and SMEs that have a number of small packages delivered from mailorder outlets.
Unfortunately though very few of them have Goods In Transit insurance (GIT) and most probably haven't informed their motor insurers that they're using their vehicle for business. It'll all be fine until they have a damage or loss claim against them, or they're involved in an accident. Their insurers are likely to refuse any claim.