The term “grassroots” is often abused. Frequently politicians use it to curry favour with their electorate.
The term was coined at the beginning of the 20th century in the USA. It referred to organisations driven by ordinary people working together to highlight a particular cause or movement.
True grassroots movements build their support and influence from the public. They are driven by ordinary individuals.
The promoters and organisers of a “grassroots” movement are unlikely to be public figures.
More recently there have been “AstroTurfing” movements; the name makes a play on the artificial grass used in sports fields.
“AstroTurfing” groups disguise themselves as grassroots movements but in fact the strategy and objectives are controlled by non-grassroots organisation.
An “AstroTurfing” organisation is much more likely to have well known public figures/organisations fronting it.