Why is this query in SSMS showing columns/tables as numbers?

Question

Here's a modified example of a query I found under 'Recent Expensive Queries' in SQL Server Management Studio:

SELECT "Col1856", "Col1857", "Col1858", "Expr1041" 
FROM 
    (SELECT "Col1856", "Col1857", CONVERT(nvarchar(50), "Col1862",0) "Expr1041" 
     FROM 
         (SELECT "Tbl1010"."user_id" "Col1848", "Tbl1010"."first_name" "Col1849", "Tbl1010"."last_name" "Col1850" 
          FROM "Web"."dbo"."users" "Tbl1010") Qry1854,
         (SELECT "Tbl1004"."cart_id" "Col1856", "Col1863", "Tbl1004"."date_stamp" "Col1859", "Tbl1004"."isQuote" "Col1871", "Tbl1004"."isSavedForLater" "Col1872", "Tbl1008"."accountNum" "Col1878", "Tbl1008"."s_id" "Col1876" 
          FROM "MyDB"."dbo"."orders" "Tbl1004", "Web"."dbo"."sites" "Tbl1008" 
          WHERE CONVERT(nvarchar(50), "Tbl1004"."code",0) = "Tbl1008"."code") Qry1880 
     WHERE "Col1857" = "Col1848") Qry1881 
ORDER BY 
    "Col1879" ASC, "Expr1041" ASC

The actual syntax doesn't matter but I'm having trouble tracking where this query is actually running due to taking a lot of resources.

What's the reason for it looking like this instead of just using the column/table names themselves?