Compare that to the days or even weeks it's going to take you to migrate to a client-server database platform as soon as you need to scale to two webservers. All the queries that need to be tested and modified as necessary... potentially different table structures... the migration of data... no thanks.
Most projects will never need to scale to two web servers. The ones that do will be successful enough to have the resources to migrate.
But I guess this all depends on whether it's B2B (likely not to have that many customers), B2C (potentially more users), or a hobby project (gimme operational simplicity!). And many other variables. YMMV!