Rental space for breeding and caring stag beetles are provided by some shops. The rental space here means a monthly rent service for a tiny space to put cases for adult insects or bottles for larva. You may doubt who spend their money to rent a tiny space for stag beetles, but there is certainly a demand for it.

As an example, you can see pictures in the below link.
ランバージャック（Tokyo）
Their rent fee is size dependent:
4,500 Yen/Month, W900×D450×H600 (mm)
6,800 Yen/Month,  W900×D450×H900 (mm)

Customer’s demand seems following two types: 1) Their family do not agree to have insects in their home and 2) They need air-conditioner to breed non-Japanese stag beetles, but they cannot prepare it in their home.

1) Their family do not agree to have insects in their home
If the family also enjoy to breed stag beetles, that is the best case (ref.1). However, that is not always the case. The family might dislike stag beetles, fluit flys (occurs in the cage) or smells (also occurs in the cage). Customer’s demand coming from this reason would not be a few (ref.2-4).

2) They need air-conditioner to breed non-Japanese stag beetles, but they cannot prepare it in their home
To breed and care stag beetles coming from southern area, air-conditioner is required in winter otherwise they cannot pass the season. Another reason for some species is to maintain temperature in summer season not to be too high. In both cases they have to run air-conditioner for 24 hours a day. If they cannot prepare it but wish to breed and care those stag beetles, they will be a customer for the service.

The shops that provide rental space for breeding/caring stag beetles are not only in big cities. Those shops are in Tokyo, Osaka, Aichi prefecture, Ishikawa prefecture and Nagasaki prefecture as far as I found on the internet. The demands seems everywhere in Japan.

References
1. The Japan Times, Sep 30, 2001
2. Over 60% people do not like insects (written in Japanese, N=1,000, MyNavi news, 2012)
3. In university, 46% of males like insects, but only 23% of females do (written in Japanese, N=130, males/females=unknown, Kyushu University, 2012)
4. In elementary school, 85% of boys like insects, but only 35% of girls do (written in Japanese, N=230, boys/girls=50/50, Gifu University, 2007)