I'm a very good back-end developer. I hate front-end fiddly bits. I can do it, I just hate it. (If you live for seven levels of LESS code, more power to you.)
Yes. A lot of back-end devs would rather chew glass than debug for four browsers, plus mobile devices.
These days front-end =/= Javascript[2] by a long shot (maybe yours is, but blame the person who made that decision for your project).
1. I don't know if that's still true. If it is, then I'm glad I no longer have to deal with MySQL.
2. GWT had strong-typing since forever. Not that I'm endorsing it, but it's still front end. I do recommend TypeScript
That's still true, as I recall. To avoid this nonsense, you need to change the sql_mode - either globally in the server config, or only within your session by issuing an SQL query.
Documentation: https://dev.mysql.com/doc/refman/5.6/en/sql-mode.html#sqlmod...