What makes MS Access attractive compared to SQL Server or other advanced database systems ?
Easy to deploy. No database server required on client machines. Just need to copy the database file (.MDB).
File based database. Easy to copy to different folders and take backups.
Built in feature to develop forms and reports. It is easy to develop fully functional database applications using MS Access itself. The easy to use reports wizard allow to create simple reports.
Simple user interface. It is easy to create or modify tables using the MS Access software.
All In One package - the MS Access software has all features available within one software (design tables, write and execute queries, generate reports, design forms etc). There is no need to open different software to perform differnet tasks on database. (Database systems like SQL Server has different tools to perform differnet tasks - like Entrerprise Manager, Query Analyzer etc)
Less targetted by hackers - most of the hackers who attack the public web sites usually target advanced database systems like SQL Server or Oracle. Also, since the features offered by MS Access are less than advanced systems like SQL Server, there are less options to hack MS Access database. Many of the SQL injection attacks will not work on Access databases due to the limited feature set.
The need for NO server software on the client machines and ease of deployment make MS Access the attractive platform for small and medium scale applications.