Can't speak to this specific case, but often this is done to help founders exercise shares/pay taxes on gains. Still a kind favor, but it's usually not a Nuemann-esque private jet purchase.
The loan was collateralized by shares, not used to purchase shares. Also the founder got a sweetheart deal on the interest rate.
“ The loan [to our founder] accrues interest at a rate per annum equal to the long-term federal rate established pursuant to Section 1274 of the U.S. Internal Revenue Code as in effect on November 8, 2019 (which was equal to 1.93% per annum), is secured by our Founder’s Class A units in Bumble Holdings and any net cash proceeds of such pledged units to the extent received by Beehive Holdings III, LP, and allows for repayment at any time”
“ The loan [to our founder] accrues interest at a rate per annum equal to the long-term federal rate established pursuant to Section 1274 of the U.S. Internal Revenue Code as in effect on November 8, 2019 (which was equal to 1.93% per annum), is secured by our Founder’s Class A units in Bumble Holdings and any net cash proceeds of such pledged units to the extent received by Beehive Holdings III, LP, and allows for repayment at any time”