LONDON — The practice of office workers pitching in to buy a gift for a departing colleague — especially one with decades of service — is an old tradition.

But when staff members at the Tate Modern and Tate Britain art galleries in London were asked this week to contribute to buy a gift for the Tate group’s departing director, many raised eyebrows over the present: a sailboat.

The timing was awkward. The call for contributions came as the Tate group, which operates four museums and art galleries across the country, was in pay negotiations with staff.

The situation highlighted concerns over widening inequality in Britain before a general election in June. As in other Western countries, questions have been raised over the concentration of the benefits of economic growth with the elite, as employee rights have eroded and wages have flatlined.