The Garden Centre Group (GCG) has begun charging for entry to its restaurant play areas.
In the first month, the group brought in £105,000 in fees, enabling it to give £35,000 to the National Society for the Prevention of Cruelty to Children, with 50p from each admission charge going to the charity. It costs £1.50 per child at GCG's 40-plus play areas.
Regional manager Peter Burks said: "Some play areas were just too busy. This decision to charge thins people out a bit. You do get the occasional person who sits there for four or five hours and brings their own packed lunch or buys just one cup of coffee."
He added: "We do kids' parties and we're trying to make more use of the play areas as well as being what was a free attraction without charging too much to keep numbers under control."
Doncaster-based House of Play has built around 40 play areas for GCG since April 2010. The areas are typically for 20 children, aged seven and under, and have enclosed seating for parents.
Sky Trail: Children's adventure course built at Planters Garden Centre in Tamworth
Planters Garden Centre has built a ú160,000 Sky Trail adventure course at its Tamworth centre.
Entrance is ú3 per person or ú10 for a family. Representative Dave Mann said: "We cater for all age groups. We have an over-60s voucher day on Wednesdays and now this has brought in families and groups like the Scouts, and for events."
Thirty people are allowed on the structure at any one time and the attraction, manufactured by Innovative Leisure, brought in more than 1,000 people a week during the summer.
A recent 60-per-cent-off Groupon offer helped to bring in new Birmingham customers, Mann added.